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Continued interest in bioactive alkaloids led to the isolation of two undescribed alkaloids, ophiorrhines F ( 1 ) and G ( 2 ), from the aerial parts of Ophiorrhiza japonica. Their structures were elucidated based on spectroscopic methods, electronic circular dichroism, and calculated NMR with DP4+ analysis. These two alkaloids represent key biological genetic intermediates in the formation of ring C in the ophiorrhines. Compound 1 exhibited good inhibition on LPS-induced B cell proliferation with an IC 50 value of 0.38 μM and showed significant selective inhibitory activity on a B cell proliferation response with a selective index of 548.42. A preliminary study indicated that 1 may have a new mechanism of immunosuppression.

The first chain-Like vibralactone derivative, vibralactone Z 4 ( 1 ), together with three known ones ( 2-4 ), were isolated from cultures of the basidiomycete Boreostereum vibrans . Vibralactone Z 4 ( 1 ) is likely to be a key intermediate from 3 to 4 in their biosynthetic pathway. It showed a weak cytotoxicity to human cancer cell line SW480 (IC 50 29.2 ± 1.38  μ M).

Three new vibralactone derivatives, namely vibralactones U-W ( 1 - 3 ), together with vibralactone ( 4 ), have been isolated from cultures of the basidiomycete Boreostereum vibrans . Their structures were determined on the basis of spectroscopic methods and literature data. All compounds showed no activities to five human cancer cell lines.

Two monoterpenoid indole alkaloids, ophiorrhines A (1) and B (2), were obtained from plant Ophiorrhiza japonica BI. Their structures were elucidated by extensive spectroscopic methods and single crystal X-ray diffraction. Compounds 1 and 2 possess a novel spirocyclic ring system. Its biosynthesis pathway is proposed. Compound 2 exhibits potent inhibitory activity against concanavalin A (Con A) induced T cell proliferation and lipopolysaccharide (LPS) induced B lymphocyte cell proliferation with IC 50 values 13.3 and 7.5 μM, respectively. Compound 1 exhibits significant inhibition specifically against the LPS-induced proliferation of B lymphocyte cells with IC 50 value 18.6 μM.

Five vibralactone derivatives containing γ, δ, ε-lactone cores, namely vibralactones X (1), Y (2), and Z 1 -Z 3 (3-5), together with the known vibralactone, have been isolated from cultures of the basidiomycete Boreostereum vibrans. Compounds 3-5 possessed a novel bis-γ-lactone group which was found in vibralactone derivatives for the first time. Compounds 3 and 5 exhibited moderate cytotoxicities to human cancer cell lines referring to that of cisplatin., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Three new podocarpane diterpenoids, namely anemhupehins A-C (1-3), together with four known analogues (4-7), have been isolated from aerial parts of Anemone hupehensis. Their structures were characterized based on extensive spectroscopic data. Compounds 1 and 4 showed certain cytotoxicities against human cancer cell lines.